New York Times journalist Michael Moss spent 3½ years working out how big food companies get away with churning out products that undermine the health of those who eat them. He interviewed hundreds of current and former food industry insiders — chemists, nutrition scientists, behavioral biologists, food technologists, marketing executives, package designers, chief executives and lobbyists.

What he uncovered is chilling: a hardworking industry composed of well-paid, smart, personable professionals, all focused on keeping us hooked on ever more ingenious junk foods; an industry that thinks of us not as customers, or even consumers, but as potential “heavy users.”

How do the food giants do it? Moss’ central thesis is that junk food is a legalized type of narcotic. By deliberately manipulating three key ingredients — salt, sugar and fat — that act much like drugs, racing along the same pathways and neural circuitry to reach the brain’s pleasure zones, the food and drink industry has created an elastic formula for a never-ending procession of lucrative products.

As Moss explains, the exact formulations of addictive junk foods (and drinks) are not accidental but calculated and perfected by scientists “who know very well what they are doing.” Their job is to establish the necessary “bliss point,” the precise amount of sugar, fat or salt guaranteed to “send consumers over the moon.”

Sugar, with its “high-speed, blunt assault on our brains,” is the “methamphetamine of processed food ingredients,” he believes, while fat is the opiate, “a smooth operator whose effects are less obvious, but no less powerful.” Without salt, he observes, “processed food companies cease to exist.”

There’s nothing earth-shatteringly new in Moss’ assertion that sugar, salt and fat are the unholy trinity of bad food. Food campaigners on both sides of the Atlantic have been saying as much for decades. But the nutrition debate is evolving, and this book is behind the curve. In both the U.S. and U.K., the characterization of saturated fat as a dietary antichrist is being challenged, not by the junk food industry, which makes a mint from spewing out supposedly healthy low-fat products, but by nutritionists and scientists. For instance, a recent review of scientific studies on fat, published in the American Journal of Clinical Nutrition, concluded that “there is no convincing evidence that saturated fat causes heart disease.”

The problem here is that Moss doesn’t even reference this discussion, merely damning fat in a generic way. So it sounds as if he believes that natural foods that contain it, such as cheese, cream and red meat, are devils incarnate. Many health commentators will have no problem signing up to the argument that the chemically hardened, industrially refined and wholly corrupted oils used to make products such as potato chips and fried chicken are undeniably bad for us, but Moss’ all-out attack on fat is more contentious.

Indeed, this failure to draw a distinction between processed junk and natural food is the flaw that runs through this book and weakens its otherwise worthwhile attack. Sugar, salt and fat get lumped together in physiological terms as addictive substances.

On sugar, however, Moss is on strong ground. Only sugar processors have the brass neck to present it as anything other than an ingredient we would do well to eat as little of as possible, so shining a light on it is most welcome. In recent years, the presence of wanton quantities of sugar in popular processed foods, such as breakfast cereals, has largely been overshadowed, even hidden, by the public health establishment’s obsession with fat. Currently, sugar is the dietary baddie that we can all agree to hate.

But in the case of salt, which Moss appears to condemn as an unalloyed dietary disaster, he shoots himself in the foot by pointing out that more than three-quarters of the salt Americans eat comes from processed food. Where is the evidence to show that this ingredient, which we have had in our diets for millennia, is a problem when consumed in small quantities in homemade food? Does anyone really get addicted to the salt they add as they cook?

Ultimately, the reader is left wondering whether Moss actually enjoys eating, or whether, after years of listening to food industry personnel, he has simply come to view it as a minefield of threatening, and less threatening, substances.

The book relies heavily (and at times tediously) on interviews with, and little pen portraits of, industry insiders, many of whom go out of their way to avoid their own company’s products. He uses these people and their anecdotes to tell the story, but this slows the book down, and gets in the way of analysis.

Moss sees his book as “a wake-up call to the issues and tactics at play in the food industry,” and it does succeed brilliantly in evidencing the systematic venality of corporate junk food and drink interests. It’s naive, he warns us, to think that we can make them behave more responsibly. “Making money is the sole reason they exist,” he writes. But as “a tool for defending ourselves as we walk through those doors,” his book is less convincing.

Readers may find themselves asking what Moss thinks we can do, other than being generally empowered by the insight he has given us into industry dirty dealings. I longed for him to urge his readers to “jerf” (just eat real food), or urge us to look beyond the well-stacked potato chip, confectionery and soda aisles so kindly provided by our large food retailers, and explore outlets that are part of a growing alternative vision for our food system.

Moss ducks that opportunity: “They may have salt, sugar and fat on their side, but we, ultimately, have the power to make choices,” he says. If only it was that simple.